Ponsonby's library, housed in the 114-year-old Leys Institute buildings, will close from 5pm on Friday because it would be dangerous in an earthquake.
Auckland Council, which owns the two buildings, has known the buildings were potentially earthquake-prone since last year.
Now a seismic assessment has confirmed that risk, finding structural issues that mean they would be unsafe to occupy in the unlikely event of a quake.
The two buildings house the Leys Institute Library and Gymnasium, serving the Herne Bay, St Marys Bay, Ponsonby and Freemans Bay suburbs. The library is believed to be the oldest in suburban Auckland.
The council says while there's no immediate risk to the public, the building would be a danger in the unlikely event of an earthquake so the "necessary decision" has been made to close it down.
Options will be considered to restore the buildings and make them safe and fit for purpose - although no timeline has been given.
The Leys Institute buildings were built in 1905 and 1906 and have been used as a library and community space since then. They were gifted to the council in 1964.
The buildings are registered as Category 1 historic places by Heritage New Zealand, and are considered to be of outstanding historical significance, meaning any strengthening work would need extensive planning and consents.
• After a quake, can we tell if a bigger one is coming?
• Latest earthquake-prone buildings identified by Auckland Council in Grey Lynn, St Marys Bay
• Revealed: Parts of NZ to be hit hardest by our next big quake
• Auckland: Where unknown volcanoes lie beneath the surface
Council director of customer and community services Ian Maxwell said there was a very low likelihood of earthquakes in Auckland compared to other parts of the country.
"There is no immediate risk to people currently using the buildings. The buildings are considered safe under normal conditions."
However in the event of an earthquake there would be a risk - and public safety had to be the main priority.
"The Leys Institute buildings are wonderful examples of Auckland's heritage and closing buildings that are a cornerstone of local community life is a difficult decision. They have a very long history of serving Aucklanders but unfortunately, it's time for us to move out for the time being."
Alternative locations are being provided for library, gym and community services. No staff jobs will be affected.
A mobile library will be on hand from 10am-4pm this Saturday, Monday and Tuesday for returns and limited borrowing.
The library will also operate outside the Leys Institute some days in January, to be confirmed on the libraries website.
A boutique pop-up library is expected to open in the nearby retail area in February.
In 2017, new earthquake-prone legislation was introduced by the Government.
It divided the country into zones based on seismic risk. Auckland was categorised as low risk, meaning the council only had to identify buildings as potentially earthquake-prone if they were unreinforced masonry buildings or built before 1976.
Under the law building owners, including Auckland Council, must make earthquake-prone buildings compliant within 35 years. For heritage buildings, this stretches to 45 years.
The council has around 2500 buildings and structures across Auckland for which it is carrying out detailed seismic risk assessments.
About 350 assessments have been completed; the remainder are expected to be complete by 2021.